Wire clenching-nail.



No. 734,163. PATENTBD JULY 21, 1903. G.'A. CURTIS. WIRE GLENGHING NAIL.

APPLICATION FILED JUNE 1, 1903. N0 MODEL.

I 5 a a wzlnekszses: J wenZ/bp I mm 290.44 Ww 3; 7%?

UNITED Patented July 21, 1903.

STATES PATENT OFFICE.

GEORGE A. CURTIS, OF READING, MASSACHUSETTS, ASSIGNOR TO CHARLES F. BAKER, OF BOSTON, MASSACHUSETTSf WIRE C-LEN CHING-NAIL.

SPECIFICATION forming part of Letters Patent No. 734,163, dated July 21, 1903. Application filed June 1,1908. Serial No.159A39. (No model.)

To all whom it may concern:

'Be it known that I, GEORGE A. CURTIS, of Reading, in the countyofMiddlesex and State of Massachusetts, have invented certain new and useful Improvementsin Wire Clenching- Nails, of which the following is a specification.

This invention relates to wire clenchingnails intended to be used chiefly by cobblers in repairing boot and shoe soles; and it has for its object, first, to provide a clenchingnail of such form that the nail will possess the maximum strength at the curve or hook where the clenching-pointbends in the act of clenching and will be free from liability to twist or turnin the leather while being driven, and, secondly, to provide a clenching-nail the manufacture of which will involve only the minimum waste of material in the shape of burs requiring removal and will reduce to the minimum the wear of the point-forming tools and the strain on the machine.

The invention consists in the improvements which I will now proceed vto describe and claim.

Of the accompanying drawings, forming a part of this specification, Figures 1 and 2 represent elevations of a nail embodying my invention taken from different points. Fig. 3 represents a view similar to Fig. 2, showing the form of the clenched nail. Fig. 4: repre- -sents a section on line 4 4 of Fig. 1. Fig. 5 represents a section on line 5 5 of Fig. 1. Fig. 6 represents a view similar to Fig. 1, showing the nail as it leaves the dies and before the removal of the burs.

The same letters of reference indicate the same parts in all the figures.

Myimproved nail is made from wire, of iron, steel, brass, or any other suitable metal, preferably cylindrical in crosssection. The penetrating portion of the nail is provided with semi-oval sides on, which intersect and form acute-angled edges a a. At opposite edges of the penetrating portion are lateral projections b 1), extending longitudinally of the nail and beyond the outline of the stock or body of the nail and formed as fins or wings, the lower ends of which join the edges a of the penetrating portion, while their sides ex 50 tend in opposite directions from the oval sides a. One object of the said projections is to reinforce and strengthen the edges of the upper part of the penetrating portion where said portion is bent in the operation of clenching, as indicated in Fig. 3. Another object of the lateral projections is attained by the substantially fiat surfaces presented by said projections atthe edges of the semi-oval sides, in that said surfaces serve to guide the penetrating portion of the nail and prevent it from turningor twistingin the leatherwhen the nail is beingdriven. Thelowerportionsofthesides of the projections are inclined inwardly toward the point of the nail, so that they are merged into the sidesa and edges a of the penetrating portion and constitute continuations of said sides and edges. Hence the projections readily displace the material into which the nail is driven, so that no additional force is required to drive the nail. I prefer to form the 7c said projections b b as V or wedge shaped extensions of the body portion 1), as shown in the drawings, said, projections extending below the upper portions of the oval sides a a and terminating, preferably, at about the center of the length of said sides. The outer edges of the projections b b are curved inwardly and join the edge a of the penetrating portion, as indicated in Fig. l.

Important advantages resulting from the form of my improved nail shown in the drawings are as follows: First, the reduction caused by said form in the quantity of the waste material displaced in the shape of burs by the dies which form the penetrating portion. Heretofore in nails of this character the acute-angled edge a has extended practically to the upper end of the penetrating or oval-sided portion of the nail, the result being that the burs which areinevitably formed 0 along the entire length of the acute-angled edge a have heretofore been much greater in length, and therefore in waste, than the burs formed in the manufacture of myimproved nail, the extent of said burs being limited 5 by the extent of the acute-angled edge a, so that the burs occur only below the extensions b, as shown in Fig. 6, which represents a nail as it leaves the dies and before the removal of the burs. Secondly, the reduction to the minimum of the wear on the tools which form the penetrating portion and of the strain on the machine. ever, to the form of projecting fins or wings here shown, as the same may be variously modified to produce the efiect of guiding the 5 penetrating portion during the operation of driving and to strengthen the bent portion of the nail without departing from the spirit of my invention.

Having thus explained the nature of the IO invention and described a way of constructing and using the same, although without attempting to set forth allof the forms in which it may be made, I declare that what I claim is- A wire clenching-nail comprising a body I do not limit myself, howportion, a penetrating portion having semi- [5 oval sides, and lateral projections extending longitudinally of the nail, said projections extending from opposite edges of the penetrating portion and beyond the outline of the stock, the sides of said projections presenting 20 substantially flat surfaces at the edges of the semi-oval sides.

In testimony whereof I have affixed my signature in presence of two witnesses.

GEORGE A. CURTIS. Witnesses:

O. F. BROWN, R. BULLOCK. 

